Selle Royal bought Brooks last year.
http://www.brookssaddles.com/ I have not heard any factual info regarding quality degradation, just the "my friend told me......." stories, as Pokey says "stinky applesauce"
Apparently they are using somewhat thinner leather, but perhaps the leather on the older saddles was too thick! A properly cared for Brooks should outlast your desire to keep it, and certainly outlast any "new' saddle on the market today.
If the Brooks fits you, you will keep it for a long time. Prepare it properly, treat it well and it could become the most valuable piece of equipment on your bike.
http://www.wallbike.com/Products.html#Brooks
http://www.sheldonbrown.com/leather.html